I've used all of them.
New genuine factory mount with chain= useless/noisey as the mount fails and the chain eats throught the rubber (my chain broke under power, ruined the handbrake assembly and my underpants!). The drive home was equally terrifying
The solid billet mount= very noisey & cracked crossmember as the diff twists unless you use solid moustache bar mounts.
RT type with urethane mount= shaving of urethane mount to get correct driveline angles which results in weakening of the mount.
The SWM mount although expensive is the best solution, do it once and do it right. It uses an OEM rubber mount encapsulated in the crossmember, even if the bush completely disintergrates the mount still works with very little play.
It's rubber so the noise is very quiet, same as a factory mount without the eventual clunk as it starts to give way.